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Discovery and Period Analysis of Seven Variable Stars
Polakis, T.
Tens of thousands of images have been acquired during the course of asteroid photometry observations at Command Module Observatory (MPC V02). Nightly sets of these images were analyzed using a software routine that locates field stars whose brightness shows anomalously high photometric scatter. A total of 32 variable stars were identified by this …
Multi-color Photometry of the Hot R Coronae Borealis Star and Proto-planetary Nebula V348 Sagittarii
Landolt, A. U.; Clem, J. L.
A long term program of precision photoelectric UBVRI photometry has been combined with AAVSO archival data for the hot, R CrB-type hydrogen deficient star and proto-planetary nebula, V348 Sgr. CCD data also are described. Since V348 Sgr is one of only four hot R CrB stars, it and other group members deserve continued attention by observers.
The First BVRcIc Precision Observations and Preliminary Photometric Analysis of the Near Contact TYC 1488-693-1
Caton, D. B.; Hill, R.; Samec, R. G. +1 more
TYC 1488-693-1 is an ~F2 type (T ~6750 K) eclipsing binary. It was observed in April and May 2015 at Dark Sky Observatory in North Carolina with the 0.81-m reflector of Appalachian State University. Six times of minimum light were determined from our present observations, which include two primary eclipses and four secondary eclipses. In addition,…
New Variables Discovered by Data Mining Images Taken During Recent Asteroid Photometric Surveys at the Astronomical Observatory of the University of Siena: Results for the Year 2017
Arena, C.; Bachini, M.; Succi, G. +5 more
This paper continues the publication of the list of the new variables discovered at Astronomical Observatory, DSFTA, University of Siena, while observing asteroids for determining their rotational periods. Further observations of these new variables are strongly encouraged in order to better characterize these stars, especially those showing non-o…
A Photometric Study of the Near-Contact Binary XZ Persei
Michaels, E. J.
Presented are two sets of multi-band CCD photometry of the Algol-type binary XZ Persei. Photometric solutions were derived using the Wilson-Devinney program for each dataset. The solution results indicate XZ Per is a semi-detached, near-contact binary whose less-massive secondary star fills its Roche lobe. Asymmetries in the light curves were mode…
A Photometric Study of the Eclipsing Binary QT Ursae Majoris
Michaels, E. J.
Presented are the first multiband light curves of the eclipsing binary QT Ursae Majoris. The light curves were analyzed using the Wilson-Devinney program to find the best-fit stellar model. Asymmetries in the light curves required spots to be included in the model. The solution results give a Roche Lobe fill-out of 13%, which is consistent with a …
Seventeen New Variable Stars Detected in Vulpecula and Perseus
Furgoni, R.
I report the discovery of seventeen new variable stars in the Northern Sky: three eclipsing (GSC 02129-00759; GSC 02129-00947; GSC 02869-02559), one eruptive (GSC 02856-02521), ten pulsating (2MASS J19305329+2558520; GSC 02129-00537; 2MASS J19323543+2524000; 2MASS J19263580+2616428; HD 275169; GSC 02869-00313; GSC 02869-01981; GSC 02856-01391; GSC…
I-band Measurements of Red Giant Variables: Methods and Photometry of 66 Stars
Moon, T. T.
New measurements of IC and V-IC are presented for 66 bright red giant variables. This is the first stage of a program to measure sufficient numbers of such stars that also have well-determined Hipparcos parallaxes with a view to calibrating the TRGB in the IC band as a tool for accurately measuring distances to nearby galaxies.
A Demonstration of Accurate Wide-field V-band Photometry Using a Consumer-grade DSLR Camera
Maravelias, G.; Eggenstein, H. -B.; Kloppenborg, B. K. +2 more
The authors examined the suitability of using a Digital Single Lens Reflex (DSLR) camera for stellar photometry and, in particular, investigated wide field exposures made with minimal equipment for analysis of bright variable stars. A magnitude-limited sample of stars was evaluated exhibiting a wide range of (B-V) colors taken from four fields bet…
The Pulsational Behavior of the High Amplitude d Scuti Star RS Gruis
García, J.
RS Gruis is a high-amplitude delta Scuti-type variable star with a mean amplitude of almost half a magnitude in V and a period of almost 3.5 hours. The most recent study of this star by Derekas et al. (2009) suggests the presence of a low-mass dwarf star companion close to the variable star with a period of 11.5 days. Rodriguez et al. (1995) have …